____ we are careful, we can't do our work ____.
Take and it will make you better.
认为“以古为镜,可以知兴替;以人为镜,可以明得失”“水能载舟,亦能覆舟”的封建帝王是( )
用所给单词的适当形式填空。①There was an____ (argue) happened between Tom and Jack last night.②Lucy never ____ (have) a walk after supper every day.③The people in Iraq keep fighting for their own ____ (free).④The teenagers have to work hard because of the____ (press) from their parents.⑤They tried their best to find the____ (solve) because they want to solve the problems.
下列关于实验现象和生成物的叙述,错误的是( )