keep a straight face in a sentence

Examples

1. Senack keeps a straight face the entire time.
2. Cook keeps a straight face as he explains exactly why Spiggott is unsuitable for the role.
3. He's very good at it, but it was still difficult to keep a straight face ."
4. Still, for me it is hard to look at this thing and keep a straight face.
5. Cellucci, who had served in the Senate for six years, struggled to keep a straight face.
6. That he will keep a straight face is a testament to his ability as a puppet.
7. The trick is to keep a straight face.
8. I say, trying to keep a straight face.
9. "He doesn't laugh at anything, but if you watch it he barely keeps a straight face.
10. Rove says, trying to keep a straight face.