想問一句句子有冇錯grammer

As we all know, the dairy contamination status has not yet been under control.

The grammar is correct.
For the word “status” I would suggest to change to “crisis” since this is a critical issue while “status” just has a moderate meaning of “condition”.

If we change to “crisis”, then it is no problem to use together with “under control”.
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After this scandal, the government should better have a stricter scrutiny to prevent similar cases happen again.

scrutiny有冇用錯?? – No, it is no problem to use scrutiny.
Another word which should be more suitable is : surveillance – this word has a meaning of supervising and inspection which is more frequently used in a system.

In fact for both scrutiny or surveillance, we can add “system” after it to make it a noun phrase and to better express the idea to want to convey.