在 is an auxiliary verb. One of the usages is to express an ongoing action.
Nǐ zài zuò shénme?
What are you doing?
Zhāng nà zài shuìjiào.
Zhang Na is sleeping.
The adverb 还
When 还used before verbs, it means “still”and “also”. When it used before “在”, it can be used to indicate that something is continually occurring.
Tā hěn lèile, dànshì tā háishì xué zhōngwén.
Although she was very tired, she was still learning Chinese.
Búyào shuōhuà, wǒ nǚ'ér hái zài shuìjiào.
Be quiet! My daughter is still sleeping.
The particle 了
One of the most common usages is to express the completion of an action.
Nǐ jīntiān zǎoshang chīle shénme?
What did you eat this morning?
Wǒ zuótiān wǎnshàng kànle zhōngwén shū.
I read a Chinese book last night.
The auxiliary verb要
要 has quite a lot of meanings in Chinese. It can be used before verbs to indicate a future action.
Xīngqíwǔ wǒ yào xué zhōngwén.
I’m going to learn Chinese this Friday.
Míngtiān nǐ yào zuò shénme?
What are you going to do tomorrow?
Chinese time expression rule
In Chinese sentence structure, big time often used before more specific time. The order will be like: year-month-week-day-time
Wǒ míngtiān xiàwǔ shí diǎn qù zhǎo nǐ.
I will meet you at 10 o’clock tomorrow afternoon.
Jīntiān shì wǔ yuè èrshí rì xīngqísān.
It’s Wednesday, May 28th today.
Word order in Chinese
The basic word order in a Chinese sentence is as follows:
Subject+ Adverbial(time, place, manner, etc)+ verb+ object
Zhāng nà xīngqísān qù kàn diànyǐng.
Zhang Na is going to watch a movie on Wednesday.
Wǒ míngtiān yào qù gōngzuò.
I’m going to work tomorrow.