Nếu a+2c>b+c  thì bất đẳng thức nào sau đây đúng?

a.-3a>-3b  b.a^2 > b^2    c.2a>2b

Nếu a+2c>b+c  thì bất đẳng thức nào sau đây đúng?

.  Identify the one underlined word or phrase - A, B. C or D - that must be changed for the sentence to be correct.

30.Frank is usually swimming before work, but this morning he is jogging.

                   A                                       B     C                              D

31.Once when I was ten. I used to get sick and went to the hospital.
                 A       B           C                               D

32.Hung leaves the house at 5.15 and arrive in the field at  exactly 6.00.

               A                      B               C                               D

33.Tommy play tennis with me  every afternoon.

                   A              B     C               D

34.I always goes to school by bike. 

          A        B                   C      D