While every possible means __________ to prevent the river pollution, the river in my hometown has still not been restored to its past beauty.

While every possible means __________ to prevent the river pollution, the river in my hometown has still not been restored to its past beauty.

#100447

is tried

are tried

has been tried

have been tried

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— Was the driving pleasant when you went to Mexico last summer? — No, it ＿＿ for four days when we arrived, so the roads were very muddy.

#104410

was raining

had been raining

would be raining

rained

 ---It_____ for a whole week. I think it’ll stop soon. ---Hard say. We’re getting into the rainy season now.

#99639

has rained

has been raining

is raining

will rain

To add to the festive atmosphere，the park ______with some grand lights during some special festivals.

#104350

dots

will be dotted

are dotted

have dotted

 This ship set sail and gradually disappeared where the sea ________ the sky.

#99500

meets

reflects

catches

connects

— Why do we get up so early?— If we _______ the flight we would have to stay here for another day.

#99228

miss

would miss

missed

had missed