What classes of words don’t have the concrete lexical meaning and possess the grammatical meaning only?

particle

72. 
    What is the only non -finite form of the verb that combines with the modal verb to form a compound modal verbal predicate?
    
73. 
    It has more of the nominal peculiarities gerund
    
74. 
    What forms do infinitive and gerund comprise?
    

Perfect/indefinite and active/passive

75. 
    What follows such verbs as to hope, to promise, to refuse, to offer, etc?
    

These verbs followed by to infinitives

76. 
    Which of the verbals combines the features of the finite verb with those of the adjective and the adverb?
    

The participle combines the characteristics of a verb with those of an adjective or an adverb; the gerund and the infinitive combine the characteristics of a verb with those of a noun.

77. 
    Which of the verbals morphologically coincides with the gerund?
    
78. 
    What qualities does participle combine?
    

The participle combines the characteristics of a verb with those of an adjective or an adverb; the gerund and the infinitive combine the characteristics of a verb with those of a noun.

79. 
    What is the form of the underlined word, e.g. The writing of the diploma turned out to be more time consuming than she had expected.
    
80. 
    Where can such forms as been, laughed, written, etc. can appear?
    

Perfect form

81. 
    Which of the verbals has no category of aspect?