81.  And I want to know the deffrence between " further " and " farther."

82.  I don't know which is right.

83.  I don't know use them .

84.  You said you didn't know how to lose weight quickly.

85.  I come to know when we do everything, we don't give up until we finish it.

86.  I don't know but I think: the same as the stars, knowledge is also inexhaustible .

87.  Of course, you all know what happened later: Feng stoke on the pile of sand.

88.  Though I know the final is nothing with me, I glad to join in the match, because it gave me a chance to practise.

89.  Now we will say good-bye to the lab and we know a quite condition is very important for us to have lessons.

90.  Now you know the reason.