短文改错 71... two years before.. before.→ago 72. .. am walking..am→was 73. . cheerful waved to... cheerfulcheerfully→ 74.... her houses. houses-house→ 75.... has been made..去掉been 76.... the rule. .the→a 77.... but some of us...but→and78. stopped quick ..前加for 79... quite concerning. concerning-concerned, 80.... making her days...her→our电