homeless.

② If we_________(catch) the last fish one day, we ____________ ( hear ) it crying.

③ If we____________ ( cut down) the last tree one day, where would the birds be?

Step 3

Conclude the structures of three unreal situations again to consolidate their memory.

条件从句 if从句谓语形式 主句谓语形式

与现在事实相反

与过去事实相反

与将来事实相反

Step 4

Play a game and do some exercises.

Click the number and play a game.

if 条件从句 主句 I am the boy throw the rubbish into the dustbin I am the driver not throw the waste from the moving car I am the student not climb over the guardrail(护栏) Step 5 Let's talk.

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Step 6 Homework