has been studying 

studied

was studying 

has studying 

has studied 

have walked 

has walked

have walking  

have been walking 

has been walking 

you don't have to park here.

you couldn't park here.

you have to park here.

you shouldn't park here.

Because the action of baking has been happening for a long time and is still in progress.

Because the focus is on the ongoing activity of baking. 

Because the result of a completed action (the cake is ready) is relevant to the present (you can try a slice).

She might knows the answer. 

I have to leave early today.

You mustn’t forget your ID.

You should call her.

have been being 

was being 

have been

have being 

was

finished 

has finished 

have finished 

have been finishing 

You don’t have to take notes during the meeting.

You shouldn't take notes during the meeting.

You must not take notes during the meeting.

You might not take notes during the meeting.

She may come late.

She will come late.

She must come late.

She can come late.

She might come late.

have been drinking

have drunk

drank 

has been drinking 

has drunk