Special sentences creating new activities.

§1. This special meaning is only needed for one case. If activities are created by the sentence

Counting is an activity on numbers.

then this happens via the regular meaning of "to be", because "activity on numbers" is a valid kind of value. But this:

Describing is an activity.

can't be handled that way because "activity" is not a valid kind. And so we handle this case through a special case of "X is Y" which applies only if Y matches:

<bare-activity-sentence-object> ::=
    <article> activity |
    activity

§2. 

int ActivityRequests::new_activity_SMF(int task, parse_node *V, wording *NPs) {
    wording SW = (NPs)?(NPs[0]):EMPTY_WORDING;
    wording OW = (NPs)?(NPs[1]):EMPTY_WORDING;
    switch (task) {
        case ACCEPT_SMFT:
            if (<bare-activity-sentence-object>(OW)) {
                <np-unparsed>(SW);
                V->next = <<rp>>;
                <np-unparsed>(OW);
                V->next->next = <<rp>>;
                return TRUE;
            }
            break;
        case PASS_1_SMFT:
            Activities::new(Kinds::unary_con(CON_activity, K_object),
                Node::get_text(V->next), TRUE);
            break;
    }
    return FALSE;
}