mid April, see the beautiful Cherry Blossoms in Washington DC and get great photos because you'll be led to all the best spots by the best guides. The annual spring bloom in DC is a magical time and this tour promises to provide the very best tour opportunity for you!

1．Which tour would provide you with a sightseeing boat?

A .The Lights Night Tour B .Best Mount Vemon & Arlington Cemetery Tour

C .The Best Minibus Tour D .The Blossoms Tour

2．What is special about The Best Minibus Tour?

A .Its price is not fixed. B .The best time to take it is at night.

C .The tour guide accompanies you. D .You can get great photos of cherry.

3．Which date suits The Blossoms Tour most?

A .July 4 B .August 15 C .March 27 D .October 8

B

When a leafy plant is under attack，it doesn't sit quietly．Back in 1983，two scientists，Jack Schultz and Ian Baldwin，reported that young maple trees getting bitten by insects send out a particular smell that neighboring plants can get．These chemicals come from the injured parts of the plant and seem to be an alarm．What the plants pump through the air is a mixture of chemicals known as volatile organic compounds，VOCs for short．

Scientists have found that all kinds of plants give out VOCs when being attacked．It's a plant's way of crying out．But is anyone listening？Apparently．Because we can watch the neighbors react．

Some plants pump out smelly chemicals to keep insects away．But others do double duty．They pump out perfumes designed to attract different insects who are natural enemies to the attackers．Once they arrive，the tables are turned．The attacker who was lunching now becomes lunch．

In study after study，it appears that these chemical conversations help the neighbors．The damage is usually more serious on the first plant，but the neighbors