Раздел a грамматикa и лексика а прочитай текст. выбери из таблицы варианты правильных ответов соответствующие указанным номерам а1-а6 так, чтобы они грамматически соответствовали содержанию текста. обведи выбранный вариант. viruses (8) … (present) a special challenge to medical treatment. traditional vaccines (9) … (consist) of either the weakened or the heat-killed virus proteins. while such vaccines (10) … (be) quite successful against some infections, they fail to cope with others. the problems in traditional immunization (11) … (sparkled) interest in new and improved vaccine models. researches now can insert a gene from a pathogen (возбудитель инфекции) into a piece of dna. when this (12) … (inject) into issues, a protein that (13) … (stimulate) an immune response (14) … (produce). a. 1 a) presents b) are present c) is present d) present с a. 2 a) is consisting b) were consist c) had consist d) consist a. 3 a) have been b) is c) are d) were ад a. 4 a) sparkled b) sparkles c) sparkle d) have sparkled ад a. 5 a) injected b) injects c) is injected d) are injected б a. 6 a) stimulated b) stimulates c) is stimulating d) were stimulating с a. 7 a) is produced b) had produced c) were produced d) produced ад