More attention must be paid _________ the endangered animals..
Cell phones _______ by more and more teens and many new functions _______ to them nowadays.
--- The couple _______ after 10 years’ marriage. --- What a pity. Their child may suffer a lot from this.
--- I need some fresh air, so I’m going out for a walk. --- _________.
—Shall I help you?—Sure. Such a difficult case is ______ I could handle myself.
Everyone likes to develop a close relationship ______ we trust each other.