He was very __________ of my safety.
Nearly all the streets are in ________lines, running from east to west. Those that run from north to south are called avenues.
—Hi, this way, please.—OK. I sometimes have no sense of ________when I arrive at the crossroad.
Along with the letter was his promise ________he would visit me this coming Christmas.
I was just talking to Margaret when Jackson________.
Now many crops can be improved ________different species of plant, such as rice, wheat.