ADVERB | VERB + SUSTAINADVERB➤no longer不再能維持◇The soil was so badly eroded it could no longer sustain crop production.土壤侵蝕得厲害,不能再種莊稼了。➤barely幾乎不能維持▸➤indefinitely無限期保持▸➤still仍然支撑VERB + SUSTAIN➤be able to, can能夠/可以維持▸➤be unable to, cannot不能夠/不可以維持▸➤help (to)有助於維持▸➤be difficult to, be hard to難以為繼◇This relationship would be very difficult to sustain.這一關係會難以為繼。➤be impossible to不可能維持➤be enough to, be sufficient to足以/足夠維持➤be necessary to有必要維持