There is only one real formal way to say hello in Mandarin Chinese, and whilst you can translate literal meanings from many English greetings the only one that is used is 你好 (nǐ hǎo). Below are some introductory sentences, greetings, how to introduce yourself and how to say bye. There is a lot to take in here, but I hope it useful. Please suggest ways to continue conversations below in the comments.
Hello
你好
nǐ hǎo
Hello (Polite & Formal: when speaking to someone older or of more importance)
您好 Nín hǎo
Hello (to a group)
你们好
nǐmen hǎo
Hello (more oftenly used on the phone)
喂
wèi
Instead of saying 'My name is' (我的名字是 / wǒ de míngzi shì) Chinese people usually say I am..... when introducing themselves.
我是...
wǒ shì...
How are you?
你好吗
nǐ hǎo ma?
How are you doing?
你怎么样?
Nǐ zěnme yàng?
How are you today?
你今天好吗?
nǐ jīntiān hǎo ma?
Did u sleep well last night?
昨晚睡得睡的好吗?
zúo wǎn shùi de hǎo ma?
I am Good
我很好
wǒ hěn hǎo
And You?
你呢?
nǐ ne?
Good Thank You
好谢谢你.
hǎo xièxie nǐ.
Nice to meet you!
幸会
Xìng huì!
The weather is nice today, isn't it?
今天的天气真好,是不是?
jīntiān de tiānqì zhēn hǎo, shìbùshì?
Saying Hello at Different Times of Day

Good Morning
早上好
zǎoshanghǎo
or
早安
zǎo ān
(literally 'early peace')
- mainly used in Taiwan
Good Afternoon
下午好
xiàwǔhǎo
or
午安
Wǔ ān
- mainly used in Taiwan
Good Night
晚上好
Wǎnshàng hǎo
or
晚安
Wǎn ān
- mainly used in Taiwan
Saying Goodbye in Mandarin
I have to go now.
我必须走了。
wǒ bì xū zǒu le.
Goodbye
再见
zàijiàn
Byebye
拜拜
Bàibài
See You Later
回头见 jiàn
huítóu
or
待会儿见
dài huìr jiàn
I need to go to sleep
我需要睡觉
wǒ xūyào shuìjiào
See you Tomorrow
明天见
míngtiān jiàn
Please leave comments below, with other phrases and conversation starters for everyone to share.
This is a quick post to help with your vocabulary when talking about things in time. This post relates to weeks, months and years. If you are wanting to talk about things in terms of Days please check my previous post.
一月
yī yuè
January
二月
èr yuè
February
三月
sān yuè
March
四月
sì yuè
April
五月
wǔ yuè
May
六月
liù yuè
June
七月
qī yuè
July
八月
bā yuè
August
九月
jiǔ yuè
September
十月
shí yuè
October
十一月
shí yī yuè
November
十二月
shí èr yuè
December
禮拜 / 星期
lǐ bài / xīng qī
week
這個星期
zhèi gè xīng qī
this week
上個星期
shàng gè xīng qī
last week
下個星期
xià gè xīng qī
next week
月
yuè
month
這個月
zhèi gè yuè
this month
上個月
shàng gè yuè
last month
下個月
xià gè yuè
next month
年
nián
year
今年
jīn nián
this year
去年
qù nián
last year
明年
míng nián
next year

Having had to experiment and explore Chinese grammar today, with the help of a couple of my friends on twitter, I learnt the way to incorperate colours into sentences. First of all though lets go through a couple of the basic colours. Each colour ends with 色 sè
白色 (báisè) White
黑色 (hēisè) Black
红色 (hóngsè) Red
黄色 (huángsè) Yellow
蓝色 (lánsè) Blue
绿色 (lǜsè) Green
紫色 (zǐsè) Purple
橙色 (chéngsè) Orange
Colours are descriptive of an object and when used as a description you put the suffix 的 de following the colour. This makes it clear that you are talking about the preceeding object being that colour. If you are just saying that something generic is a colour you need not place 的 (de) at the end of the colour. But if it is in reference to something specific then 的 de is required.

zhèxiē huā shì zǐsè de
These flowers are purple.

zhè zhī xióngmāo shì hēisè hé báisè de
This panda is black and white.

Zhōnghuá Rénmín Gònghéguó guóqí shì hóngsè hé huángsè de.
The Chinese* Flag is red and yellow.
Hopefully this gives you a starting grasp of colours and how they are used within Mandarin sentences. I have only just learnt this today, and am glad to share it with you.
Charlie
* 中华人民共和国 (Zhōnghuá Rénmín Gònghéguó) actually means The People's Republic of China.
Photo Source
Flickr
Flickr
Flickr
Flickr
Ok so today as promised I said I would place here what I felt I had learnt through my Mandarin studying today.
I came across a phrase in Rosetta Stone that I hadn't before and had to google to understand it.
quite big

zhè gè niǎo dàn hěn dà
This egg is quite big.
鸟 (niǎo) actually means bird (something else I have just found out. :). So I'm not sure if this is right in this context. However it does hope to illustrate the point.
Let us try another one, just so you get the point;

zhè gè píngguǒ hěn dà
This apple is quite big.
But this sentence should actually of course be:
zhè gè píngguǒhé hěn dà
This applecore is quite big.
Hope you ejoyed my discovery of the phrase: Quite Big. 很大 hěn dà.
Charlie.
Photo Source:
Flickr
My friend Gabriel, over at learnchinesetoday.info has written a guest post based about histoical figure Qin Shi Huang and his influence on the Chinese Language.As some of you may know, the official title of 'emperor' was first used by Qin Shi Huang several hundred years before Christ. At the end of the 7 warring states period, the Qin state had conquered most of the other states and unified China properly.
Historically speaking, it was true that under the leadership of Qin Shi Huang, life was harsh and difficult. Many historians viewed him as a dictator who ruled across the land with an iron hand.
Untold numbers died working to build the Great Wall of China.
And yet paradoxically, it was Qin Shi Huang who had help create a lasting legacy in Chinese history. He had played a huge role in maintaining the stability and longevity of Chinese culture.
What did he contribute? Well, before the Qin dynasty, the 7 different states each had their own languages, rules and customs. After unification, Qin Shi Huang went about creating one common language. Everyone had to read and write the same Chinese characters.
This seemingly simple but profound change in standardizing the Chinese language would bind and enable the Chinese people to maintain their identity and culture for thousands of years to come.
If he had not done so, China might have developed differently. The Chinese people might have different languages and writing not unlike Europe (the French, British, etc.)
There were many more changes Qin Shi Huang made that help shaped the future course of Chinese imperial system, but suffice to say, Qin Shi Huang was not merely known as just a brutal dictator.
So the next time you wish to learn Chinese, think back to this historical figure who had contributed much to this ancient language.