詞組及地道用法：
1、date back to?
?Our present ideas about the motion of bodies date back to Galileo and Newton.
延伸
? ...-A perpetual struggle to discover how the University works that goes back to the earliest civilizations.
2、pure thought
?...one could work out all the laws that govern the universe by pure thought.
自己造句：?It's impossible to mediate the dilemma by pure thought.
3、lead weight 吊錘
?If one drops two bodies that don't have much resistance,such as two lead weights,...
4、be proportional to?
proportional ? ? ?properly related in size or degree or other measurable characteristics; usually followed by `to'
?This states that a body will accelerate,or change its speed,at a rate that is proportional to the force.
5、have something doubled
?Thus the force between two bodies would be twice as strong if one of the bodies(say, body A)had its mass doubled.
6、have+次數(shù)+something
?One of the bodies had twice the mass,and the other had three times the mass..
7、for instance
?For instance,one playing Ping-Pang on the train,...
8、accord with
?...it didn't accord with his idea of an absolute God.
9、given和provided
given：介詞，其后只能跟名詞
?Given his age,he did it quite well.
provided:連詞或形容詞，形容詞意為“提供的”
?...,provided they used a good clock.
?Please put your litter in the bin provided.
?To get these features working you first have to install the software provided.
