Find: а) synonyms spacecraft, to call, artificial, significance, area, man-made, satellite, purpose, complicated, importance, space vehicle, ex¬plorer, aim, to guide, to offer, researcher, investigation, to incor¬porate, sophisticated, to propose, to determine, exploration, to define, to gather, to control, to collect, to name, to include, dis¬trict, moon; b) antonyms special, upper, unmanned, natural, last, manned, unequal, conventional, distant, first, lower, civil, equal, inefficient, military, near, efficient, artificial.
a) spacecraft- space vehicle; to call- to name; artificial- man-made; significance- importance; area- district; satellite- moon;
purpose- aim; complicated- sophisticated;
explorer- researcher; to guide- to control; to offer- to propose;
investigation- exploration; to incorporate- to include;
to determine- to define; to gather- to collect;
b) special - conventional;
upper- lower; unmanned- manned; natural- artificial;
last- first; unequal- equal; distant- near;
civil- military; inefficien- efficien;