He devoted himself _______ to his research and got many achievements.

While reading, Helen has a habit of stopping _____ to give her long and flowing hair a smooth.

Under criminal law, people who      carry and use large numbers of fake banknotes will be sentenced to less than three years in prison.

------So you gave her your phone?------_____, she said she’d return it to me when she could afford her own.

I'd like the colour, but I’m afraid it’s ___expensive.