. We laugh at jokes，but seldom about how they work.
| A．we think | B．think we | C．we do think | D．do we think |
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It was ___ he came back from Africa that year ___ he met the girl he would like to marry.
| A．when; then | B．not; until | C．not until; that | D．only; when |
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Bob ran the 100 meters in 9.91 seconds, and I have not seen ___ this year.
| A．the best | B．better | C．the most | D．more |
.
My parents told me to look forward ___ road signs while walking on the street.
| A．seeing | B．to seeing | C．to see | D．see |
.
. ___ by the advances in technology, many farmers have set up wind farms on their land.
| A．Being encouraged | B．Encouraging | C．Encouraged | D．Having encouraged |
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It is none of your business ___ other people think about you. Believe yourself.
| A．how | B．what | C．which | D．when |