Should I say "in Summer" or "in the Summer"?
Can you guys give me examples please?
Ok, now I see that both ways are possible, so let me change the question.
When should I say "in the summer" and when should I say "in summer"?
Can I have examples please?
In summer we go to the seaside.
In the summer of 1973 I studied at Coimbra.
When seasons are used as metaphors, there is nearly always a 'the': In the autumn of his career he spent too long online.
Why don't you follow riquecohen's suggestion now and try some examples of your own?