aggressiveness

"That gentleman is a stranger to me.  Children are taught not to talk to strangers."

"She moved toward the door."

"The bird's nest was a concrete example of how strong and carefully constructed things can be. "

"The reasons are various."

"an aggressive policy, war, person, nation"

"He has a propensity for lengthy discussions of certain favorite topics."

"Quality of life is usually determined by health, education, and income."

"The label on the fertilizer bag listed ammonium sulfate as a key ingredient to help plants grow. "

"The solubility of sugar in hot water is much higher than in cold water, so it dissolves faster when the water is warm. "

"The birds had built an amazing structure out of sticks and various discarded items."

"The complicated instructions on the new software difficult me from completing the project on time. "

"The dissolve between the shot of the teacher writing on the board and the shot of the students' attentive faces was smooth and effective. "