1. His handwriting is quite hard to read.

-> be (quite) adj to V

2. She always does her homework very carefully.

-> does là động từ (cần trạng từ)
 

3. Jane is nearly old enough to stay at home alone.

-> be adj enough to V: đủ...để

4. At present, these televisions are only available in Japan.

-> be available: có sẵn

His handwriting is quite difficult to read. 

She always does her homework very carefully.

Jane is almost old enough to stay at home alone. 

Currently, only these televisions are available in Japan.