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When ___ help, one says “Thank you” while when _________ help, one asks “Can I help you?”
| A．offered; offered | B．offering; offered |
| C．offering; offering | D．offered; offering |
It rained heavily in the south,__________ serious flooding in several provinces.
| A．caused |
| B．having caused |
| C．causing |
| D．to cause |
According to the recent research, heavy coffee drinking and heart attack is not necessarily __________ and effect.
| A．reason |
| B．impact |
| C．fact |
| D．cause |
The following day she didn’t go to the club. __________, she walked her dog in a park nearby.
| A．Therefore | B．However | C．Instead | D．Besides |
In the botanical garden we can find a(n) __________ of plants that range from tall trees to small flowers.
| A．species | B．group | C．amount | D．variety |
Many animals and plants, which couldn’t __________ the sudden change of the climate, died out. Dinosaurs are one such example.
| A．add to | B．turn to | C．adapt to | D．lead to |