1. I can't get through.
电话打不通。
还能这样说：
The line isn't free.
The number is busy now.
应用解析：
get back 回来;取回;报复;
get behind 落后;支持，帮助识破，看穿;
get by 维持生活;走过，通过;躲过;欺骗;
get by on 靠……过活
2. I'm afraid the line is out of order.
线路好像出问题了。
还能这样说：
I'm afraid I've been cut off.
There is something wrong with the line.
应用解析：
hold the line 不挂断电话;
in the line of duty 在执行任务时;
line of business 经营范围;
in line with sth. 与……类似或一致
3. I'm afraid it's bad connection.
恐怕电话连接不好。
还能这样说：
I'm sorry we seem to have a bad connection.
Maybe there is a fault on the line.
谚语：
A bad workman always blames his tools.
不会撑船怪河弯。
4. I'm afraid we have a crossed line.
恐怕线路串线了。
还能这样说：
The lines seem to be crossed.
I doubt our line has got crossed with someone else's.
谚语：
No cross, no crown.
无苦即无乐。