Well Amir, 'is anything to go by' means 'in our experience' or 'in the experience of the person writing' or 'in the experience of the person speaking'.

Another example of 'is anything to go by' could be: you're standing on a station platform, you're looking at your watch, the train is late, you go up to a guard and say: 'When is the next train to London?' And the guard might say, 'Well, if previous trains are anything to go by, it will be half an hour late', meaning that his previous experience of the trains running late is about thirty minutes.

Another example would be if, perhaps, we invited a well-known pop star onto our programme, Britney Spears, for example and we said, 'If we had Britney Spears on the programme, do you think we would get lots more listeners' letters asking us questions?' And our producer might say, 'Well, if last week's programme with Phil Collins is anything to go by, yes we would.'

So in his experience in something similar is anything to go by. So it begins with if: 'if x is anything to go by then... something else.' So remember how to construct that: it's 'if' and 'is anything to go by', 'then', and then the concluding sentence.

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