9) 强调关系：
in fact; especially;
particularly;moreover;naturally;
what is more important; in reality;
certainly; of course;
indeed; in particular;
not to mention...;
believe it or not;
undeniably; other thing being equal;
it is certain/sure that...;
to be strict; to be true;by definition;
definitely; undoubtedly;
without a doubt; in truth, in any event(不论怎样);
without reservation(毫无保留地);
obviously, not only.. but(also...), both...and...
10) 条件关系:
if;unless;
lest;provided that;if it is the case;
in this sense;once...;
if possible;
if necessary;if so;if not all; if anything.