Here is something many students tend to make mistakes:
[be/am/is/are/was/were] are very frequently used words in English. They share the same translation in Chinese: Shi, which means, no matter the subject is I/you/they/he/she/it/we…we just say Shi, present tense or past tense. Chinese have other simpler ways to express tense.
In many cases [be/am/is/are/was/were] is not translated.
When the pattern is like [be + noun/pronoun], we translate be as Shi.
When the pattern is like [be + adjective], be is not translated.
We will learn more later.
In what occasion we will need to add a complement at the end?
There are no specific rules for this in Chinese. Most of time a complement is something we want to emphasize, like an adverb. For example:
He drives really fast!
In Chinese, an adverbial modifier such as [really fast] should be put ahead of the verb [drive]. But in this case the speaker obviously wants to emphasize [fast], so the proper expression is like this:
He drives de really fast.
The word [de] in Chinese indicates a modifying relationship, suggests [really fast] modifying [drive].
Again, many modifiers are clauses, in both English and Chinese. They are long, but we still have to relocate the long clause to be ahead of its modifying object. For example:
Why do you want to buy the shoes since you cannot afford them?
[since you cannot afford them] is an adverbial clause, we need to find out which element it modifies — it is [want to buy]. So we need to say this clause first, then say [want to buy], like this:
You since cannot afford them, why want to buy the shoes?