四、It is + 形容词+ that
that 引出一个主语从句，it 是无人称主语 例：显然，这些电流会使磁铁中心产生热。
It is evident that these currents will obvious clear
generate heat in the core of the magnet.
例：在磁铁中心很可能会产生涡流电流。
It is likely that eddy currents will be possible
produced in the core of the magnet.
It is + 动词+ that
例：需要注意/明白的是，这种能量是不能消 失的， 只能转化成其它形式。 It should be noted that this energy can realized not be destroyed, only changed into other forms.
例：假定气缸中气体温度为定值。 It is assumed that the gas temperature in the cylinder is constant.
It is + 动词/形容词+ that
例：最好尽可能地把这些电流除掉。 It is desirable that these currents should be essential eliminated as far as possible.
三、It is + 形容词+不定式
is
• It was
+
seems appears
+ easy + to do sth.
proves
becomes
It is +
possible impossible
+பைடு நூலகம்to do sth.
It is +
necessary unnecessar
y
+ to do sth.
= This deepens the hole.
二、enable, allow, make…+ 不定式
Enable, allow, make, cause, permit Safety valves allow/permit the steam to
escape. 安全阀能使蒸气（从锅炉中）排出 好的生产方法能使工厂生产更多的汽车。 Good production methods enable the factory to manufacture more cars. 显微镜能使科学家们观测非常小的物体。 A microscope enables the scientists to examine very small objects.
1.3 科技英语中 的一些常用句型
1
一、make +名词+形容词
这样会使问题变得容易些. • This makes the problem easy/easier. 这样能使金属更硬些. • This makes the metal harder/hard.hardens 这样能使金属变长。 • This makes the metal longer.
It is + 形容词+不定式
It is +
useful useless
+ to do sth.
It is +
usual unusual
+ to do sth.
It is + common + to do sth.
这些形容词都是带有主观评价色彩的，如：
easy， possible / impossible， useful / useless ， necessary / unnecessary ， usual / unusual
例：已经决定在几个月内开始生产。 It is decided that the production should arranged planned begin in a few months.
例：已知，……
众所周知，…… It is known that ……
据证，……
proved
例：应当注意到/应该看到/应当知道，…
enable, allow, make…+ 不定式
enable, allow, make, cause, permit 温度计能使医生（为病人）测体温。
A thermometer enables the doctor to measure body temperature. 伸缩接头能使管子延长或缩短。 Expansion joints allow/permit the pipes to expand or contract. 安全阀能使蒸气（从锅炉中）排出。 Safety valves allow/permit the steam to escape.
It should be noted
that ……
will
realized
noticed
appreciated
例：可以证明，…
It can be shown
that ……
proved
demonstrated
五、句末 + ing 子句
连接两个陈述句的一种方法 ① 同 and 的意思一样； ② 相当于 since 的意思，进一步解释； ③ 说明第一句话的后果或时间的接续。
enable, allow, make…+ 不定式
热使金属熔化。 The heat caused the metal to melt.
= The heat makes the metal melt. 火车速度太快，使其在弯道处出轨了。
The speed of the train caused it to leave the rails on the curve. = The speed of the train made it leave the rails on the curve.
= This lengthens the metal.
make +名词+形容词
这样能使螺栓更紧些。 • This makes the screw tighter.
= This tightens the screw. 这样能使洞更深些. • This makes the hole deeper.