by a canvas

(in boat racing) by a small margin

（賽艇比賽中）以毫厘之差

under canvas

&I{Nautical} With sails spread.

&I{【航?！縸 揚(yáng)帆的

In a tent or tents.

露營(yíng)：在一個(gè)或多個(gè)帳篷里