They have been planting trees this month. 这个月来他们一直在植树。
 Car sales have been shrinking recently. 汽车销量近来一直在下降。
Vera has been trying to learn Chinese for years. 维拉努力学汉语已有好几年了。
He has been sleeping for ten hours. 他已经睡了十个小时了。
Jim has been phoning Jenny every night for the last week. 上星期，吉姆天天晚上都给詹妮打电话。
The two parties have been trying to unite since the New Year. 自从新年以来，双方就一直在试图联手。