#include <bits/stdc++.h>
using namespace std;
#define MAX 100001
long long dp[MAX],sums[MAX];
int t,k;
int main()
{
    cin >> t >> k;
    for(int i = 1 ; i < k ; i++)
    {
        dp[i] = 1;
        sums[i] = sums[i-1] + dp[i];
    }
    dp[k] = 2;
    sums[k] = sums[k-1] + dp[k];
    for(int i = k+1 ; i < MAX ; i++)
    {
        dp[i] = (dp[i-1] + dp[i-k])%1000000007;
        sums[i] = (sums[i-1] + dp[i])%1000000007;
    }
    while(t--)
    {
        int a,b;
        long long result = 0;
        cin >> a >> b;
        result = (sums[b] - sums[a-1])%1000000007;
        cout << result << endl;
    }
}