词义辨析。

    A) have a look / have a look at

1. Can I _____ the photos of your family?

2. —I have a new pen. 

    —Let me _____ .

3. May I _____ what's on television?

    B) on one's way back / by the way

4. _____ home, he saw a girl crying.

5. _____ , have you seen John lately?

电焊钳外壳有裂纹会导致何种后果？