mood

[Jesse Huang]

(1) Tom is studying now. He must have been studying for more than 2 hours. (right?)

(2) Tom played TV game in the morning, but he should have been studying then. (right?)

(3) Tom played TV game in the morning, but he should be studying then. (right?)

[MikeNewYork]

(1) Tom is studying now. He must have been studying for more than 2 hours. (right?)

(2) Tom played TV game in the morning, but he should have been studying then. (right?)

(3) Tom played TV game in the morning, but he should be studying then. (right?)

1. Correct

2. Either "a TV game" or "TV games". Otherwise correct.

3. Same as #2 for TV game. The second clause should be "should have been studying then". It is in the past.

[Jesse Huang]

How about this sentence:

Tom played TV games in the morning, but he should study then.

[MikeNewYork]

How about this sentence:

Tom played TV games in the morning, but he should study then.

Nope. You are still mixing tenses. The verb "played" puts the scene in the past. "Should study" is present to future.

[RonBee]

You could say:

• Tom played TV games in the morning, but he should have been studying.

You wouldn't really need a time marker, but you could put one in there.

:)

[Tdol]

For variety, how about 'Tom played TV games in the morning when he should have been studying'?

[Android]

How about this sentence:

Tom played TV games in the morning, but he should study then.

played - is past tense, study - present.

...but he should have been studiyng then.

Or:

Tom is playing ....blah blah... but he should be studiyng.

OR:

Tom is playing ....blah blah... but he should study.

:)