if引导条件状语从句时(即作“如果”意思说时)要遵循“主将从现”(主句用一般将来时,从句用一般现在时)的原则
应该为Travelling by air will be the first choice if the price is reasonable
if引导条件状语从句时(即作“如果”意思说时)要遵循“主将从现”(主句用一般将来时,从句用一般现在时)的原则
应该为Travelling by air will be the first choice if the price is reasonable