1.   After feeding in the access code he sat back and stifled a yawn.

2.   He apologises as he stifles another yawn and tries to look interested.

3.   He sighs and stifles a yawn.

4.   He stifled a yawn then stood up and went into the kitchen.

5.   Kay shook her head and stifled a yawn .

6.   She stifled a yawn as the boss read out the sales figures.

7.   She makes no attempt to stifle a yawn.

8.   I stifled a yawn as she launched into a monologue about how she is going to become a famous star.

9.   I tried to stifle a yawn.

10.   John stifled a yawn and apologized.