雅思写作折线图常用句型举例如下：
||to begin, in 1991, the number of arrests for illegal drug use stood at 55，however, over the following three years, there was a sharp fall to 20 per year
||the number rose significantly from 1995 to 1996 to 50 per year
||1996 to 1999 saw a fluctuation in the arrest rate
which was followed by a sudden increase at the end of this period
||with the rate reaching a peak of 80 in 2000
next, the number of arrests plunged to a low of 15 in 2001
||it remained stable for the following year but then increased gradually to 20
