4.One Sunday,Mark decided to go sailing in his boat with his

4.One Sunday,Mark decided to go sailing in his boat with his friend Dan,but Dan happened to be away.Dan''s brother John offered to go instead though he did not know anything about sailing.Mark agreed and they set out to sea.Soon they found themselves in a thick fog.Mark was sure they would be hit by a big ship.Fortunately he saw a large buoy (浮标)through the fog and decided to tie the boat to it for safety.As he was getting onto the buoy,however,he dropped the wet rope.The boat moved away in the fog carrying John,who did not know how to use the radio.He drifted (漂移) about and was not seen until twelve hours later.Mark spent the night on the buoy.In the early morning he fell asleep.He was having a bad dream when a shout woke him up.A ship,the Good Hope,came up and he climbed onto it and thanked the captain.The captain told him that John had been picked up by another ship and the ship''s captain had sent out a message."Without the message I would not have found you on the buoy," he said.(本题分数：10 分.)
(1).Why didn't Mark and Dan go sailing together?( ) （2 分）A、 Dan asked his brother to go instead B、 Dan was in some other place.C、 Mark was in some other place.D、 Mark would like to go with John(2).Mark tried to tie the boat to the buoy so that( ) （2 分）A、 he could spend the night on it while John was looking for helpB、 he and John could go sailing again when the fog clearedC、 it wouldn't be hit by other shipsD、 he might be picked up by a passing ship(3).John and Mark became separated because ( ) （2 分）A、 there wasn't room for both John and Mark on the buoyB、 John couldn't control the boat and drifted awayC、 Mark thought it safe to stay on the buoy but John didn'tD、 John had to stay in the boat to radio for help(4).What made it possible for Mark to be found on the buoy?( ) （2 分）A、 John told people where to look for him.B、 John radioed to the Good Hope to get him.C、 He shouted when he caught sight of the Good Hope.D、 The captain saw him as the fog cleared(5).The word "he" in the last sentence refers to ( ) （2 分）A、 the captain that got the messageB、 the captain that sent the messageC、 John D、 Mark