积 (jī): to amass; to accumulate; to store up; (math.) product (the result of multiplication); (TCM) constipation; indigestion

He persisted in memorizing ten new words every day, and after a month he had accumulated a considerable vocabulary.

No one had cleaned the room for a long time, and dust had accumulated so thickly in the corners that it almost kept fingerprints.

Over the years he enthusiastically helped his neighbors, and in the community he accumulated a great deal of goodwill.

It had snowed all night, and a thick layer had accumulated on the roof, looking as if it were covered with a quilt.

If not cleaned promptly, the grease in the kitchen sink will gradually accumulate into a layer of sticky grime.

He persisted in saving ten yuan a day, and over several years he accumulated a not insignificant sum, finally buying the camera he loved.