拖(tuō) - to drag, to pull along; to drag out, to delay in Mandarin

拖 (tuō) is to drag something along a surface rather than lift it. A suitcase across a platform, a chair across a floor, a reluctant child towards the door: the object stays in contact with the ground, and that contact is what separates 拖 from 拉.

The figurative use is at least as common. 拖 also means to let something drag on: 拖时间 is playing for time, 拖了半年 is a job that has slipped by six months, and 拖延 is the formal word for procrastination. If a Chinese colleague says 这个项目拖了很久, nobody has touched a rope.

Two things catch English speakers out. 拉 is pulling in general, including pulling a door open or pulling someone's sleeve, so translating pull as 拖 by default gives you a picture of things scraping along the floor. And 拖地 does not mean drag the ground; it is the everyday word for mopping, from the mop being pushed and pulled across the tiles.