China recently tightened its waters controls near the Huangyan Island to prevent Chinese fishing boats from _______ in the South China Sea.

. He regretted______ to the lecture the day before. 

With so many friends        me, I had no difficulty finishing the work on time.

Beijing announced on Sunday that the date for events ____ the 40th anniversary of the normalization of China-Japan relations would be “adjusted to an appropriate time”.

After the snowstorm, mailboxes in the community were covered by snow, or _______, or lying on the ground.