You miss laying one brick and your dream house will surely collapse one day!!
Learning grammar is equated to a house-builder learning how to lay its foundation first, and then, laying brick upon brick on that strong foundation. Every brick is carefully laid to construct the complete body of the house. Hard work is required of each learner of the English Language to ensure every part of grammar is learnt. Nothing must be left out! Well, we can learn a lot from the humble ant that hard work certainly pays off.
Of course grammar is hard to learn, let alone master. There are many grammar rules. We need to learn all the structures in grammar. Imagine a house with a missing structure in it. It will be just a matter of time before it collapses. It may go unnoticed by the builder but it will surely show up one day and the fall will be great! We can avoid disappointments, embarrassment and unnecessary loss if we work hard like our tiny 6-legged friends to lay brick upon brick of the whole grammar structure needed to construct sentences that are accurate in meaning and purpose.