1.The change in__________lalgely results from the fact that__________.

2.We may blame__________.but the teal causes ale__________.

3.Part ofthe explanations for it iS that__________.

4.One ofthe most common factors/causes iS that__________.

5.Another contributing factor/cause is __________ .

6.A number of factors are accountable for this situation.

7.This might contribute to/lead to/account for the phenomenon/ problem.

8.The answer to this problem involves many factors.

9.The phenomenon mainly stems from the fact that__________.

10.The factors that contribute to this situation include__________.

11.Perhaps the primary factor is that__________.