更多upstroke例句

1. The parts are in correct mechanical balance because two pistons are on the upstroke while the other two are descending.
2. This is characterized by a long sweeping upstroke, and the recurving downstroke cuts the staff about in half.
3. During the upstroke the cup collapses inwards and allows air to pass by it.
4. After the downstroke is completed, the teeth A will cut on the upstroke, the teeth B cutting on the downstroke, etc.
5. During an upstroke this closes, and the other opens; the reverse happening during a downstroke.